反应详情

To a solution of methyl 5-(benzyloxy)-4-methoxy-2-nitrobenzoate (13.48 g, 0.0425 mol) in MeOH (700 mL) at 55° C., a concentrated solution of Na2S2O4 in water was added slowly until no more starting material was observed on TLC. The heterogeneous solution was concentrated under vacuum. The residue was treated with water (100 ml) and the mixture extracted with ethyl acetate (2×200 mL). The combined organic layers were washed with water and brine. After drying over MgSO4, the solvent was evaporated and the residue was purified on silica gel column, using ethyl acetate/DCM (1/9) as eluent to yield methyl 2-amino-5-(benzyloxy)-4-methoxybenzoate. Yield: 7.36 g (60%). 1HNMR (DMSO-d6): δ 7.34 (5H, m), 7.25 (1H, s), 6.48 (2H, s), 6.39 (1H, s), 4.91 (2H, s), 3.80 (3H, s), 3.73 (3H, s). LC-MS (ESI) m/z 288 (M+H)+.

1. concentrationThe heterogeneous solution was concentrated under vacuum
2. additionThe residue was treated with water (100 ml)
3. extractionthe mixture extracted with ethyl acetate (2×200 mL)
4. washThe combined organic layers were washed with water and brine
5. dry with materialAfter drying over MgSO4
6. customthe solvent was evaporated
7. customthe residue was purified on silica gel column